What do all oxygen atoms have in common

An atomic number of 8

Explanation:

All oxygen atoms have an atomic number of 8 in common, but could differ in mass number in their isotopes.

Examples of oxygen atoms are O16, O17, and O18. They all have an atomic number of 8, but different mass numbers of 16, 17, and 18 respectively. Thus, they are isotopes of oxygen.

weight of any object is given by

w = m*g

where m is mass of the object and g is the acceleration due to gravity.

for earth the value of g is 9.8 m/s^2 so

w=117.6 n m=12 g=?

117.6=12g => g=9.8 m/s^2

which is the force of gravity on earth.